public void CreateGoal(Goal goal)
        {
            if (goal.DueDate < DateTime.Now)
            {
                throw new ApplicationException("Goals cannot have a Due Date in the past.");
            }

            _container.Goals.Add(goal);
        }
 public void UpdateGoal(Goal goal)
 {
     _container.Goals.Attach(goal);
     _container.SetStateForEntity(goal, EntityState.Modified);
 }